Scientists from Nanjing University and University of Texas have developed a wireless tagging device that can send signals to smartphones warning consumers and food distributors when meat and other perishables have spoiled.
Food inspectors often use bulky, expensive equipment to detect harmful microbes. Scientists are investigating other approaches, including near field communication (NFC) labeling, that are both portable and dependable. NFC devices wirelessly transmit information over short distances -- usually less than 4 inches.
The scientists have created a nanostructured, conductive, polymer-based gas sensor that can detect substances called biogenic amines (BAs), which give decomposing meat its bad odor. They embedded these sensors into NFCs placed next to meats. After the meats had been stored for 24 hours at 86 degrees Fahrenheit, the researchers found that the sensors successfully detected significant amounts of BAs. The sensors then switched on the NFCs so they could transmit this information to a nearby smartphone.